Polar modulation and one-point frequency modulation systems offer advantages over other modulation systems. For example, both make use of digital devices for signal processing instead of analog devices and both operate using only a single carrier frequency. As a result, polar modulation and one-point frequency modulation employ less complex designs and consume less power than alternative systems. Both polar modulation and one-point frequency modulation are well-suited for use in mobile telephones, networkable portable computers and entertainment devices, and other portable communications devices.
Both polar modulation and one-point frequency modulation systems are dependent upon the reference clock frequency signal supplied to them. Thus, each of these systems has to be adapted to operate with the reference frequency of the device in which it is used. Unfortunately, this means that many different modulation systems have to be created for use in many different devices.
Polar modulation and one-point frequency modulation systems also are used for secondary communications systems included in telephones and computing devices, such as Bluetooth communication systems or wireless local area network adapters. These secondary systems also have to be adapted to the different reference frequencies of the systems in which they will be used. Having to design and manufacture many different modulation systems for different reference frequencies makes it difficult to exploit economies of scale, thus, making it more expensive to produce polar modulation and one-point frequency modulation systems.
In the drawings, like numerals represent like elements. In addition, the first digit in each of the three-digit reference numerals refers to the figure in which the referenced element first appears.